Recent advances in non-invasive connectivity mapping techniques, such as diffusion MRI and resting state functional connectivity, have resulted in a resurgence of interest in the investigation of the connectivity of the human cerebral cortex. The connectivity of the various cerebral cortical areas, which is only beginning to be studied in humans, has been examined in detail in the macaque monkey during the last 50 years using experimental anatomical anterograde and retrograde tracer techniques. These techniques provide exquisite detail of the origin, course and termination of axons from one cortical area to another. This experimental research, therefore, provides specific hypotheses to be tested in the human with new emerging non-invasive connectivity mapping methods, as well as a framework within which to interpret findings in the human. The human cerebral cortex poses substantial challenges because its topology is very variable and its detailed organization not very well known. Connectivity can be used to map the boundaries of anatomical subregions within large-scale systems, and holds promise as a powerful resource for defining homotopic areas across brains and between hemispheres. Nonetheless, it is worthwhile to consider the limitations inherent in these methodologies so that the limits of the conclusions drawn can be fully appreciated. We aim to bring together articles critically addressing connectivity-mapping techniques, such as diffusion tensor imaging-based tractography and resting-state functional connectivity, in the specific context of anatomical investigation. In order to make fruitful contributions to the study of neuroanatomy, the application of these techniques requires special consideration. Each technique comes with unique strengths and weaknesses, bounding the interpretation of results. For instance, what is the relationship between various measures of functional connectivity and axonal connections? And what is the appropriate scale of subdivision? Given recent developments, it is appropriate to review achievements thus far, ongoing prospects, and future limitations as applied to the complex anatomy of the cerebral cortex.
Recent advances in non-invasive connectivity mapping techniques, such as diffusion MRI and resting state functional connectivity, have resulted in a resurgence of interest in the investigation of the connectivity of the human cerebral cortex. The connectivity of the various cerebral cortical areas, which is only beginning to be studied in humans, has been examined in detail in the macaque monkey during the last 50 years using experimental anatomical anterograde and retrograde tracer techniques. These techniques provide exquisite detail of the origin, course and termination of axons from one cortical area to another. This experimental research, therefore, provides specific hypotheses to be tested in the human with new emerging non-invasive connectivity mapping methods, as well as a framework within which to interpret findings in the human. The human cerebral cortex poses substantial challenges because its topology is very variable and its detailed organization not very well known. Connectivity can be used to map the boundaries of anatomical subregions within large-scale systems, and holds promise as a powerful resource for defining homotopic areas across brains and between hemispheres. Nonetheless, it is worthwhile to consider the limitations inherent in these methodologies so that the limits of the conclusions drawn can be fully appreciated. We aim to bring together articles critically addressing connectivity-mapping techniques, such as diffusion tensor imaging-based tractography and resting-state functional connectivity, in the specific context of anatomical investigation. In order to make fruitful contributions to the study of neuroanatomy, the application of these techniques requires special consideration. Each technique comes with unique strengths and weaknesses, bounding the interpretation of results. For instance, what is the relationship between various measures of functional connectivity and axonal connections? And what is the appropriate scale of subdivision? Given recent developments, it is appropriate to review achievements thus far, ongoing prospects, and future limitations as applied to the complex anatomy of the cerebral cortex.
